Great Basin Raptor Nest Surveys

HWI conducted a Great Basin Raptor Nest Survey from 1998-2009 to reseach nesting raptors throughout northwest Utah and northeast Nevada. The study area spanned 3 million acres and included six focal raptor species, including Golden Eagles, Ferruginous Hawks, Red-tailed Hawks, Swainson's Hawks, Prairie Falcons, and Burrowing Owls. Our efforts focused on comprehensive monitoring of all active nests of focal species found within the study area, covering all suitable and accessbile habitats, emphasizing open woodland, cliff, and shrubsteppe habitats characteristic of the northern Great Basin. The study also monitored the nesting of uncommon Peregrine Falcons in the region, having documented the first eyries of this species in the region since the 1960s, as well as Common Raven nesting activities because they routinely swap nests with several of the raptor species.

Through multiple visits to observe active nests and adult behaviors, our surveyors recorded information on nest initiation (eggs laid), hatching success and initial brood size, and fledgling production (or chicks reared to at least 80% of the typical fledging age for the species). These Utah-Nevada surveys resulted in a database that included records for more than 2,500 raptor and raven nests, with roughly 2/3 of these in Utah. The database, companion GIS information, and technical reports summarizing productivity trends provided a scientifically defensible basis for making land-management decisions and developing ecosystem management plans for the region that maintain healthy raptor populations and the proper functioning of Great Basin ecosystems.

In 2008 we completed a 10-year report on our survey efforts, which raised concerns about an aggressive invasive plant named cheatgrass. These results later lead to our West Desert Raptors research.

This project was made possible by financial and logistical support from Utah Division of Wildlife Resources (UDWR), the Salt Lake Field Office and Elko District Office of the Bureau of Land Management, and the United State Forest Service Sawtooth National Forest.